[scarecrow420]

I still suspect that only encoded audio from onboard the TV (eg builtin tuner, builtin smart TV apps) would be bitstreamed out the optical output. Encoded audio (eg DD5.1) input over HDMI would be decoded by the TV and its not going to re-encode it to DD5.1 to output it. Or potentially your linux system was inputting multi channel PCM over HDMI and not encoded DD etc anyway? In which case the TV isnt going to encode that MPCM as Dolby Digitial or whatever, and the full uncoimpressed PCM cant be carried by optical (only 2 channels can)